Halogenated glycolurils



United States Patent 3,165,521 HALOGENATED GLYCOLURILS Frank B. Slezak and Irving Rosen, Painesville, and Clifford A. Neros, Willoughby, Ohio, assignors to Diamond Alkali Company, Cleveland, Ohio, a corporation of Delaware No Drawing. Filed June 21, 1962, Ser. No. 204,054 4 Claims. (Cl. 260256.4)

This invention relates to novel haloglycolurils and more specifically relates to novel haloglycolurils having particular utility as sanitizing agents for swimming pools, and to the preparation and application of these compounds.

This application is a continuation-in-part of our copending application Serial No. 635,615, filed January 23, 1957, now abandoned.

In general, the compounds of this invention may be represented by the structure:

(R3)m (H)\lX/(Rl)! )1-m 0:' 112); (H) 1n N (H) l-q (B4)]; (EDI-x (R2): (Rah wherein x, m, n, p and q=O or 1, R and R are alkyl groups and R R R and R are halogen. In most instances, R and R are the same or different lower alkyl groups such as a methyl group or other alkyl groups containing up to about 4 carbon atoms, since as the chain length increases, the compound generally shows less solubility in water and often is more difiicult to prepare. Specific illustrative compounds embodying this invention are:

1,3,4,G-tetrachloroglycoluril Cl H Cl N O= I 3:0 lac-1i;

(Elli $1 1.5-dimethyl-2,4,6,8-tetrach1oro-2,4,6,8-tetrabicyelo(3.3.1) nona-3, ione Cl CH3 Cl The compounds of this invention have a high available chlorine content and are characterized by a singular activity as sanitizers and disinfectants, i.e., in applications wherein the compound employed inhibits the growth of microorganisms on an inanimate object or surface, or at 3,165,521 Patented Jan. 12, 1965 least reduces the number of such microorganisms present thereon to a safe level. They may likewise be used as bleaching agents and in disinfecting and bactericidal applications generally, as well as in various biologicallyactive compositions such as fungicides and nematocides. Of particular interest is the efliciency of the compounds of this invention, and especially that of l,3,4,6-tetrachloroglycoluril to inhibit the growth of microorganisms such as bacteria and algae in swimming pools, or to control the number of these organisms within acceptable limits with respect to health and sanitation standards.

Halogen-containing compounds which will provide in aqueous solution large percentages of active halogen, and particularly active chlorine, are commonly used commercially as sanitizing agents for water. The use of the compounds of this invention which are normally solid materials inherently provides a significant improvement over many disinfecting agents used heretofore, including the well known, widely-used solutions of inorganic alkali and alkaline earth metal salts of hypochlorous acid. Moreover, the fact that compounds of this invention are solids provides increased convenience by way of easier handling and affords the use of less complicated and more easily operated sanitizing systems.

As mentioned previously, the compounds of this invention are characterized by their high chlorine content. For example, 1,3,4,6-tetrachloroglycoluril, which is employed most advantageously in the present invention, has a higher chlorine content generally than any other halogenated organic compound presently being offered as a swimming pool'sanitizer. Since the compounds of this invention likewise exhibit a rate of dissolution which is somewhat slower than these other halogenated organic compounds, they can be contacted with water and dissolved at a rate-which provides a closely regulated, constant percentage of chlorine to the pool over a longer period of time, without adding to, or replenishing the treating chemical The high total halogen content of the compounds of this i nvention thus allows for satisfactory disinfecting levels, even at peak periods of pool operation, by using these compounds in minimum quantities.

Generally, to prepare the compounds of this invention, a glycoluril or an alkyl-substituted glycoluril is chlorinated in an aqueous medium in the presence of an inorganic acid-binding alkali metal compound. The alkali metal compound is desirably selected from alkali metal carbonates, e.g., sodium carbonate; alkali metal bicarbonates, e.g., sodium bicarbonate; alkali metal borates, e.g., sodium borate; alkali metal silicates, e.g., sodium metasilicate; and alkali metal hydroxides, e.g., sodium hydroxide; and is preferably added to the aqueous medium in suflicient quantity to render it alkaline. Preferably, an alkali metal bicarbonate is used.

The haloglycolurils of this invention are employed as swimming pool sanitizers in amounts which will provide satisfactory disinfecting levels of residual chlorine, which levels have been found to be within the range of 0.3 to 1.0 part per million parts of water, with a range of about 0.4 to 0.8 part per million being preferred. Used at these concentrations, these compounds are non-toxic materials, dissipate no detectable chlorine odor, and are superior in their bactericidal action as compared with the effectiveness of other known halogenated organic sanitizing agents. Additionally, these compounds, used in amounts providing the desired levels of residual chlorine,

do not significantly change the pH of the pool water from the desirable range, which is about 7.2 to 8. Consequently, these chemicals do not contribute to eye irritation or to skin sensitization, which conditions are generally caused by contact with sanitized pool water with a pH different from the satisfactory range.

The haloglycolurils of this invention are likewise more stable in solution than other sanitizers, such as halogenated isocyanurates and halogenated unsubstituted and alkyl substituted hydantoins. That is to say, the residual chlorine supplied by the compounds of this invention is dissipated more slowly than is that supplied by other halogenated organic sanitizing agents. Therefore, the chlorine so supplied is available for a longer period of time, and its bactericidal and disinfecting activity is more continuously effective. Addiitonally, this property becomes even more advantageous when the retention of chlorine is measured in treated pools when exposed to sunlight. As will be shown hereinafter by specific data, outdoor swimming pools treated with compounds of this invention retain satisfactory levels of residual chlorine at least 1 /2 times longer than those treated with other organic sanitizers.

Since the compounds of this invention likewise exhibit substantial algicidal and fungicidal activity, it is not necessary to add compounds normally used as algicides and fungicides, in addition to these materials. However, if it is desired to employ such compounds, the halogenated glycolurils of this invention are completely compatible with these materials. They are also compatible with other pool additives, such as buffering agents, e.g., sodium carbonate, which may be added in minimal amounts from time to time in certain instances, to maintain the desired pH level, although the use of such buffering agents generally is not required.

Applied in the amounts required for satisfactory disinfecting levels of residual chlorine, the compounds of this invention are not even minutely detrimental to the clarity and sparkling quality of the swimming pool.

The compounds of this invention may generally be used in powdered form in sanitizing operations, the compound being confined in any suitable container and contacted with sufficient quantities of the circulating pool water to dissolve enough compound to supply the re quired level of residual chlorine to the pool. In practice, however, it is preferred to employ the compounds in the form of compressed rods, or sticks, since these materials afford a more even surface area in contact with the water, are more convenient to handle, are easier to confine, and the possibility of such solids being flushed into the pool is very remote. Additionally, the compound rods are very difiicult to break, and do not dust in shipment or in storage.

To fabricate the compounds of this invention into rods, it has been found very satisfactory to thoroughly mix the dry compound with sufiicient quantity of water to form a damp, but free-flowing powder mix. A typical mix is comprised of about 25 to 30 percent water. The blending process is accomplished at room temperature using, as apparatus, any blade-type mixer of low shearing speed, e.g., a ribbon blade mixer. The powder mix prepared is thereafter passed through a plasticizing extruder preferably fitted with corrosion-resistant parts in contact with the mix, and converted to a soft coherent plastic mass. This material is then passed through a finishing extruder and the damp, coherent extrudate is broken up into rods about 2 to 3 inches in length and about 1 inch in diameter. The formed rods are then air-dried, or oven-dried at a temperature around 80 C.

Another method which may be employed to fabricate the compounds of this invention into conveniently applied shapes is to melt said compounds and then cast them in the form of solid or hollow cylinders of variable design to provide different surface areas for use with varying water circulation systems. Thus, shapes of the N-halogen compounds of this invention may be fabricated so that a satisfactory halogen concentration may be maintained constantly in pool water being recirculated at a constant rate, a variable rate, etc. 5 In the sanitizing operation, a portion of the water being recirculated is bypassed through a bed composed of large pellets of the sanitizing compound, said bed being situated apart from the pool and near the circulation pump. The rate at which the water is allowed to flow through the bypass and contacted with the chemical can be closely controlled by metering valves, and is measured by a flow indicator. Thus, the sanitizing system can be easily adjusted to supply at a constant rate the level of residual chlorine desired. After contact with the chemical, the clear, treated water re-enters the main circulation line and is recycled to the swimming pool.

In order that those skilled in the art may more completely understand the present invention and the preferred methods by which the same may be carried into effect, the following specific examples may be offered:

EXAMPLE 1 Preparation of 1,3,4,6-Tetrachl0r0glyc0luril PART A Into 2 liters of water containing 50 gms. of sodium bicarbonate is introduced and suspended 71 gms. (0.5 mol) of glycoluril. The resultant mixture is chlorinated while continuously being agitated, sodium bicarbonate solution (150 gms. sodium bicarbonate in 2 liters of water) being added at a rate to maintain the pH of the solution between 4 and 8. Chlorination is continued until 130% of the stoichiometric amount of chlorine is introduced, i.e., a total of 182 gms. The resultant solid is separated, washed with about 1600 ml. of water, dried partially under suction for to minutes and then allowed to air dry. The resultant product weighs 132 gms. after drying. Chemical analysis indicates preparation of the desired product which contains 98.9% available chlorine as compared with the theoretical available chlorine of 101.4%.

PART B Element Percent Percent calculated actual EXAMPLE 2 Preparation of Dichloroglycoluril There is suspended in 800 ml. of water 14.2 gms. (0.1 mol) of glycoluril and the introduction of chlorine is begun, a 6 N solution of NaOH being added portionwise to maintain the pH Within the range from 7 to 8. A total of 89.2% of the theoretical amount of chlorine (based on stoichiometric amount required to form trichloroglycoluril), and 45 ml. of 6 N NaOH are introduced. The resultant material is filtered and the filtrate evaporated to dryness to yield 34.8 gms. of a white solid. This solid is washed twice with water and dried under suc tion. There results 17.1 gms. of a white solid. Chemical analysis indicates preparation of the desired C4H4Cl N4O2 and is as follows:

Element Percent Percent calculated actual 22.76 22.46 1.91 1.50 33.63 35.1 N 26.54 25. 95 Available chlorine 68. 08 69. 1

EXAMPLE 3 Preparation of 1,S-Dimethyl-Z,4,6,8-Tetrachlr0-2,4,6,8- T etrazabicyclo(3 .3 .1 )N0na-3,7-Di0ne Into 3 liters of water is introduced 56 grns. (0.3 mol) of 1,5 dimethyl 2,4,6,8 tetrazabicyclo(3.3.l)nona- 3,7-dione [Rec. trav. chim. 27, 162-91 (1908)]. Chlorine is then gradually introduced into the stirred solution simultaneously with the addition of 6 N sodium hydroxide at a rate to maintain the pH of the reaction mixture within the range from approximately 5 to 8. A total of 130% of the theoretical amount of chlorine (110 gms.) and 125% of the theoretical amount of 6 N sodium hydroxide (250.2 m1.) are added. The resultant reaction mixture is filtered and the pasty residue washed with 400 to 600 ml. of water and filtered again. The thusobtained solid is allowed to dry to yield a white powder weighing 86.8 grns. Chemical analysis indicates that it contains 78.3% available chlorine (theoretical available chlorine 88%). Chemical analysis indicates preparation of the desired C H CL N O and is as follows:

Using 1,3,4,6-tetrachloroglycoluril as a test fungicide, spore germination tests on glass slides are conducted via the test tube dilution method adopted from the procedure wherein the test chemical, in aqueous formulations at concentrations of 1000, 100, 10 and 1.0 p.p.m. is tested for its ability to inhibit germination of spores from 7 to IO-day-old cultures of Alternaria oleracea and Monilinia fructicola. These concentrations refer to initial concentrations before diluting four volumes with one volume of spore stimulant and spore suspension.

Germination records are taken after 20 hours of incubation at 22 C. by counting 100 spores. The test compound is rated on its ability to inhibit germination of half of the spores, i.e., the so-called ED-50 value, in the test drops.

Using the above procedure, ED-SO values between 0.1 and 1.0 p.p.m. are obtained, indicating a high degree of fungicidal activity.

EXAMPLE 5 The tomato foliage disease test measures the ability of a test compound to protect tomato foliage against infection by the Early Blight fungus Alternaria solani and employs tomato plants 5 to 7 inches high of the variety Bonny Best. Duplicate plants are sprayed with 100 ml. of the test formulation at 2000 and 400 p.p.m. (2000 or 400 p.p.m. 1,3,4,6-tetrachloroglycoluril, 5% acetone, 0.01% Triton X-155, balance water) at 40 lbs. air pressure while being rotated on a turntable in a spray chamher.

After the spray deposit is dry, the treated plants and comparable untreated controls (sprayed with formulation less toxicant) are sprayed with a spore suspension containing approximately 20,000 conidia of Alternaria solani per ml. The atomizer used delivers 20 ml. in a 30-second exposure period. The plants are held in a saturated atmosphere for 24 hours at 70 F. to permit spore germination and infection before removal to the greenhouse. After 2 to 4 days, lesion counts are made on the three uppermost fully expanded leaves. The data are converted to percentage disease control based on the number of lesions obtained on the control plants.

Using the above procedure, a 100% disease control is obtained at 2000 p.p.m. while 99% disease control is obtained at 400 p.p.m., thus indicating a high degree of fungicidal activity in protecting tomato foliage.

EXAMPLE 6 This test is an evaluation of the effectiveness of compounds of this invention against root-knot nematodes (Meloidogyne sp.). Composted greenhouse soil diluted by one-third with clean, washed sand is placed in /z-gallon glazed crocks and infested with 3 to 5 g. of knotted or galled tomato roots. Treatment is accomplished by mixing the test chemical intimately with the soil if a solid, or by drenching, if a liquid, paste, or of gummy consistency. The drench formulation contains 4% acetone, 0.01% Triton X-155, 0.768% test chemical in a total volume of 100 ml. of water, all of which is drenched on the test crock. Concentration of this formulation is 512 pounds per acre based on the surface area of the /z-gallon test container. The soil surface area equals 21.7 square inches, therefore, 512 pounds per acre equals 768 mg. of chemical. Lower concentrations are prepared by employing less of the test chemical in the formulation. The mixing of the solid test chemicals is accomplished by placing the infested soil and the chemical in a 20- pound paper bag and mixing thoroughly. The soil is then replaced in the crock to which is added 100 ml. of water. In the case of the drench treatment, the chemicals are mixed after 2 or 3 days as described above via the paper bag method. After treatment, all crocks are stored at 20 C., being covered with plastic to maintain moisture.

Seven days after treatment, three seedling (var. Bonny Best) tomatoes are transplanted into each crock. After three weeks in the greenhouse, the plants are removed from the soil carefully and the roots inspected for nematode galls. A rating of infection is made from 0=no galls or complete control, to 10=heavily galled roots comparable to controls. Each of the three plant root systems is rated separately and the average is multiplied by 10 and subtracted from 100 to give percent nematode control.

Using this procedure, it is observed that 1,3,4,6-tetrachloroglycoluril exhibits control of nematodes. By contrast, 1,3,4,6-tetrachloro 3a,6a dimethylglycoluril, when similarly tested, exhibits no control and is comparable to controls.

EXAMPLE 7 Non-plant parasitic nematodes (Panagrellus redivivus) are exposed to 1,3,4,6-tetrachloroglycoluril (1000 p.p.m. aqueous formulation) in small watch glasses (27 mm. dia. x 8 mm. deep) within a 9 cm. Petri dish, and results are recorded 24 hours after treatment. With the above procedure, a nematode mortality of is observed.

EXAMPLE 8 To indicate fungicidal activity of dichloroglycoluril, spore germination tests on glass slides are conducted using this compound by employing the test chemical in aqueous formulations at concentrations of 1000, 100, 10 and 1.0 p.p.m. in tests to determine its ability to inhibit germination of spores from 7 to IO-day-old cultures of Alternaria oleracea and Monilinia fructicola. These concentrations refer to initial concentrations before diluting four volumes with one volume of spore stimulant and spore suspension. Germination records are taken after 20 hours of incubation at 22 C. by counting 100 spores. The test compound is rated on its ability to inhibit germination of half of the spores, i.e., the socalled ED-50 value in the test drops. Using the above procedure, an ED-SO value of 10 to 100 p.p.m. is obtained, thus indicating a marked degree of fungicidal activity.

EXAMPLE 9 To indicate fungicidal effectiveness of 1,5-dimethyl- 2,4,6,8 tetrachloro-2,4,6,8-tetrazabicyclo(3.3.1)nona-3,7- dione, spore germination tests on glass slides are conducted using this compound by employing the test chemical in aqueous formulations at concentrations of 1000, 100, 10 and 1.0 p.p.m. in tests to determine its ability to inhibit germination of spores from 7 to 10-day-old cultures of Alternaria oleracea and Monilinia fructicola. These concentrations refer to initial concentrations before diluting four volumes with one volume of spore stimulant and spore suspension. Germination records are taken after 20 hours of incubation at 22 C. by counting 100 spores. The test compound is rated on its ability to inhibit germination of half of the spores, i.e., the so-called ED-50 value in the test drops. Using the above procedure, an ED-SO value rating against the two organisms of 10 to 100 p.p.m. and l to 10 p.p.m., respectively, is observed, thus indicating a high degree of fungicidal activity.

EXAMPLE 10 The tomato foliage disease test measures the ability of a test compound to protect tomato foliage against infection of the Early Blight fungus Alternaria solam' and the Late Blight fungus Phytophthora infestans. The method employs tomato plants to 7 inches high of the variety Bonny Best. Duplicate plants, one set for each test fungus, are sprayed with 100 ml. of the test formulation at 2000 and 400 p.p.m. (2000 or 400 p.p.m. dichloroglycoluril, 5% acetone, 0.01% Triton X-l55, balance water (at 40 lbs. air pressure while being rotated on a turntable in a spray chamber.

After the spray deposit is dry, the treated plants and comparable untreated controls (sprayed with formulation less toxicant) are sprayed with a spore suspension contain ing approximately 20,000 conidia of Alternaria solani per ml. or 150,000 sporangia of Phytophthora infestans per ml. The atomizer used delivers 20 ml. in a 30-second exposure period. The plants are held in a saturated atmosphere for 24 hours at 70 F. for Early Blight and 60 F. for Late Blight to permit spore germination and infection before removal to the greenhouse. After 2 to 4 days, lesion counts are made on the three uppermost fully expanded leaves. The data are converted to percentage disease control based on the number of lesions obtained on the control plants. Using the above procedure, the percentage disease control of Early Blight at the two concentrations is 98% and 62%, respectively. Percentage disease control of the Late Blight at these concentrations is 100 and 99%, respectively.

EXAMPLE II The tomato foliage disease test measures the ability of a test compound to protect tomato foliage against infection by the Early Blight fungus Alternaria solam'. The method employs tomato plants 5 to 7 inches high of the variety Bonny Best. Duplicate plants are sprayed with 100 ml. of the test formulation at 2000 and 400 p.p.m. [2000 or 400 p.p.m. 1,5-dimethyl-2,4,6,8-tetrachlorotrol of the Late Blight at these concentrations is 100 and 2,4,6,8-tetrazabicyclo(3.3.l)nona-3, 7-dione, 5% acetone, 0.01% Triton X-l55, balance water] at 40 lbs. air pressure while being rotated on a turntable in spray chamber.

After the spray deposit is dry, the treated plants and comparable untreated controls sprayed with formulation less toxicant) are sprayed with a spore suspension containing approximately 20,000 conidia of Alternaria solani per ml. The atomizer used delivers 20 ml. in a 30- second exposure period. The plants are held in a saturated atmosphere for 24 hours at F. to permit spore germination and infection before removal to the greenhouse. After 2 to 4 days, lesion counts are made on the three uppermost fully expanded leaves. The data are converted to percentage disease control based on the number of lesions obtained on the control plants. Using the above procedure, a disease control is observed at both concentrations employed.

EXAMPLE 12 Non-plant parasitic nematodes (Panagrellus redivivus) are exposed to dichloroglycoluril (1000 p.p.m. aqueous formulation) in small watch glasses (27 mm. dia. x 8 mm. deep) within a 9 cm. Petri dish and results are recorded 24 hours after treatment. Using the above procedure, a nematode mortality of 100% is observed.

EXAMPLE 13 To test the bactericidal activity of the compounds of this invention, each chemical is mixed with distilled water, containing 5% acetone and 0.01% Triton X 155, at a concentration of 1000 p.p.m. Five ml. of the test formulation are put in each of 4 test tubes. To each test tube is added one of the organisms: Erwinia amylovora, Xanthomonas phaseoli, Staphylococcus aureus and Escherichia coli in the form of a bacterial suspension in a saline solution from potato-dextrose agar plates. The tubes are then incubated for 4 hours at 30 C. Transfers are then made to sterile broth with a standard 4 mm. loop and the thus-inoculated broth incubated for 48 hours at 37 C. when growth is rated as follows: A=no growth, B=moderate and D=heavy growth.

Using the above procedure, at the indicated concentrations, the following results are obtained:

Growth rating of 4 organisms 48 hrs. after a 4-hr. exposure to Contest compounds at eoncn., p.p.m. Bacteneide centration, p.p.m. E. X. S.

amyZophasau- E.

com 6012' reus coli 128 A A A A 64 A A A A 1,3,4,6-tetraehloro- 32 A A A B glycoluril. 16 A A A A 8 B A A A 128 A A A A Diehloroglycoluril 64 O A A A 32 C A A A 16 B A A A 8 B A A A 256 A A A A Roecal 64 C B B A 16 C B B O r a a A 2 A Clorox 32 A A A A 8 A A A A Control D D D D 1 Roceal-benzalkonium chloride. 2 Cl0roxaqueous solution of sodium hypoehlorite.

EXAMPLE 14 This test measures the comparative effectiveness of 1,3,4,6 tetrachloroglycoluril and other halogenated sanitizing agents in inhibiting the growth of the bacterial species Escherichia coliform (E.c.) at various concentra tions.

The basic test formulation contains 0.1 g. of the test chemical, 4 ml. acetone, 2 ml. stock emulsifier solution (0.5% Triton X- in water by volume) and 74 ml. distilled water, the concentration of toxicant in this formulation being 1250 parts per million. Lower concentrations of toxicant are obtained by diluting the basic formulation with distilled water. The bacterial species is cultured on nutrient agar slants, and is subcultured for two sequential 24-hour periods to insure uniform test populations. Bacterial suspensions are made from the second sub-culture in the culture tube by addition of distilled water and gentle agitation, after which they are filtered through double layers of cheesecloth and adjusted to standard concentrations by turbidimetric measurement. Each test tube, arranged in a rack, receives the appropriate amount of the test formulation. After the test formulations have been measured into a test tube, distilled water and 6. ml. of the bacterial suspension are added to each test tube. The medication tubes are then left undisturbed at room temperature for two minutes. After this exposure period, transfers are made by means of a standard 4 mm. platinum loop to 7 ml. of sterile broth. The broth tubes are then incubated for 48 hours and for 72 hours at 29 to 31 C., at which times bacterial growth is determined by turbidimetric measurement. A reading is recorded for each test tube after shaking. These replicates of each organism serve as controls. Comparative growth calculations are made on the percent of the mean check reading. This value, subtracted from 100, gives percent control as compared to checks. Using this proce- To determine the rate of loss of available chlorine from solutions of 'l,3,4,6-tetrachloroglycoluril and other swimming pool sanitizing agents, solutions of the test chemicals are exposed to indoor (fluorescent) light and to simulated sunlight. A G.E. RS-type sunlamp is employed in the simulated sunlight test. The time periods required for a solution of 1.0 p.p.m. available chlorine to dissipate to 0.30 p.p.m. are measured, as these concentrations represent the maximum and minimum levels of residual chlorine usually tolerated in a typical swimming pool. Chlorine dissipation is determined by frequent analysis of the exposed solutions. The following results are ob- 1 Time to decrease from 1.00 to 0.30 p.p.m. available chlorine.

EIQAMPLE 16 Swimming Pool Sanitization PART A Fabrication of sanitizing chemical rds.-Eighteen pounds of 1,3,4,6-tetrachloroglycoluril and 7 pounds water are intimately mixed for 15 minutes at room temperature in a ribbon blender operated at a shearing speed of 60 r.p.m. The resulting mix is a damp, free-flowing powder. This material is then passed once through a plasticizing extruder equipped with a short, open, 2" die and a '1" spacer. Under the low pressure developed by the pla'sticizing extruder, the powder pre-mix becomes a soft, coherent plastic mass. This material is then fabricated into rods by being passed through an extruder having a ribbed barrel 14 inches long, knives in reverse spiral, and equipped with a die, 3 inches long and 1 inch in diameter. The extruder, operating at a speed of 30 r.p.m. with a semi-full screw, processes 16 /2 pounds of material per minute. The smooth, cylindrical extrudate is broken up into rods, 2 to 3 inches long and approximately 1 inch in diameter. The fabricated rods are then air-dried.

PART B Swimming pool sanitizing application-The outdoor swimming pool treated is of fiberglass construction and has a volume capacity of 35,000 gallons of water, recirculated at a rate of about gallons per minute. The cycling line is equipped with a bypass whereby a portion of the circulated water being pumped from the pool is passed through a bed of the sanitizing chemical rods, prepared in Part A of this example. The rate at which this water is bypassed through the treating bed is about 10 gallons per minute, said rate having been previously adjusted by the metering valve and checked by the flow indicator. The treated water is then remixed with the rest of the circulated water. Before being reintroduced into the pool, the sanitized pool water is passed through a sand filter. The bypass setting provides a level of residual chlorine ranging between 0.4 and 0.8 part per million, even during periods of peak pool operation. Less than one-half pound of the santitizer is consumed per day.

PART C Bacterial count of sanitized pool water.-The bacterial count is determined on several replicate samples of pool water, collected prior to the sanitizing treatment described in Part B above. The procedure used is outlined in Standard Methods for the Examination of Water and Wastewater, eleventh edition, 1960, compiled and adopted for use by the American Public Health Association, American Water Works Association and the American Water Pollution Control Federation.

Using the standard plate count test, the bacterial count of the untreated pool water averages 920 bacteria/ml.

Standard procedures are used to determine the presence of Escherichia coliform in the untreated water, using the multiple-tube fermentation technique. The agar culture slants are examined after incubation at 35 C. for 24 hours. Gram-staining indicates the presence of E. coli.

Three hours after the Sanitizing treatment of Part B above is initiated, water samples are collected and examined. It is found that the baceterial count is reduced to 14 bacteria/ml, and that gram-staining of culture slants, incubated at 35 C. for 24 hours and 48 hours, is negative, i.e., there are no virulent E. coli organisms present.

It is to be understood that although the invention has been described with specific reference to particular embodiments thereof, it is not to be so limited, since changes and alterations therein may be made which are within the full intended scope of this invention as defined by the appended claims.

What is claimed is:

1. A compound having the structure:

1 1 3. 1,5 dimethyl 2,4,6,8 tetrachl0r0-2,4,6,8-tet1'azabicyc1o( 3 .3 .1 )nona-3,7-dione.

4. Dichloroglycoluril.

References Cited by the Examiner UNITED STATES PATENTS 2,130,805 9/38 Levine 210-62 2,392,505 1/46 Rogers 2603095 2,404,096 7/46 Rogers 260309.5 2,526,477 10/50 Heimbach 260256.4 2,596,742 5/52 Vaughn et a1 260309.7 2,613,210 10/52 Hurwitz et a1. 260309.7

Adkins 260309.7

Williams 260-309.7

Adkins 260309.7

Karnlet 21062 Walters 1855 Scheer et a1 2603095 Levison et a1 1855 Kamlet 260--309.7 Slezak et a1 260309.7

IRVING MARCUS, Primary Examiner.

JOHN D. RANDOLPH, NICHOLAS S. RIZZO,

Examiners.

UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No. 3,165,521 January 12, 1965 Frank B. Slezak et a1.

It is hereby certified that error appears in the above numbered patent req'iiring correction and that the said Letters Patent should read as corrected below.

Column 7, line 63, for "EXAMPLE II" read EXAMPLE ll line 72, strike out "trol of the Late Blight at these concentrations is 100 and"; line 75, before "spray" insert a column 8, lines 37 and 38, for "B=moderate" read B=slight C=moderate column 9, line 20, for "These" read Three column 10, line 74, for "p",- second occurrence, in italics, read q in italics.

Signed and sealed this 1st day of June 1965.

(SEAL) Attest:

ERNEST W. SWIDER EDWARD J. BRENNER Aitesting Officer Commissioner of Patents 

1. A COMPOUND HAVING THE STRUCTURE: 1-((R3)M-),1-((H)(1-M)-),2-((R1)X-),2-((H)(1-X)-),3-((R)P-) 3-((H)(1-P)-),4,8-DI(O=),5-((R6)Q-),5-((H)(1-Q)-), 6-((R2)X-),6-((H)(1-X)-),7-((R4)N-),7-((H)(1-N)-), 2,6-(-(CH2)X-)-OCTAHYDRO-1,3,5,7-TETRAZOCINE WHEREIN R1 AND R2 ARE ALKYL OF UP TO 4 CARBON ATOMS; R3, R4, R5 AND R6 ARE CHLORINE; AND X, M, N, P AND Q ARE EACH NUMBERS FROM 0 TO 1, INCLUSIVE, AT LEAST TWO OF M, N, P AND P BEING
 1. 